Reverse-gear.



E@ M. SHANNON.

REVERSE GEAR.

APPLIGATION FILED FEBJZ, 1914.

Patented Feb. 23, 1915.

LWQJML N gw A E. M. SHANNON.

REVERSE GEAR.

APPLICATION FILED rmmz, 1914.

Patented Feb. 23, 1915.

2 SHEET S-SHBET 24.

mentar.

*@TE STAR@ T ELFWOOD M. SHNNON, QF PADELPHI, PEINSYLV, ASSIGNOR 'E0 T BALDWIN LOCOMOTIVE TWORKS, 0F PHILADELPHM, PENNSYLVANIA, COR,-

PRATIDN @F PENNSYLVAN, I

Vanesa-eraan.

Application led February 12, 1914.

1, is a side View of a starting cylinder illus trating my improved means for positively locking the mechanism in the positionv to which it is set; Fig. 2, is an enlarged transverse sectional view on the line a--a, Fig. 3; Fig. 3, is an enlarged sectional view on the line b-b, F ig. 2; Fig. 4, is a detached perspective view of the clutch block; Fig. 5, is a sectional view of the valve illustrated in Fig. 1; Fig. 6, is a sectional view illustrating a modification of the locking mechanism; Fig. 7, is a perspective view of the clutch block shown in Fig. 6; and Fig. 8, is a sectional view of the valve for controlling the air of the lock shown in Fig. 6.

-Referring to the drawings, 1 is the startingcylinder; 2 is the piston rod having a piston located in the cylinder l; 3 is the cross head which slides on the guide 4 se cured, in the present instance, to the cylinder casing. A lever 5 is connected to the cross head by a link 6, as shown in Fig. 1,

and this lever is attached to the valve stem 7, the valve of which is mounted in the chest 8 of the cylinder 1. The lever is also connected by a link 10 to one arm of lever 11 pivoted at 12 to the frame. The other arm of the lever is connected b a bar 12 to one arm of the hand lever 13 1n the cab of the locomotive. Thelever is pivoted at 14 and has the ordinary latch 15 which engages a segment 16. The latch is provided with a handle 17 so that, on actuating the handle,

the lever 13 can be released and can b moved to any position desired.`

After the ordinary mechanism has been moved to a given position, the piston has a tendency to move, due to the working of the valve motion, and, consequently, the cross head and the parts connected therewith are Specication of Letters Patent.

Patentamt net. ea, raie.

Serial No. 818,360.

shifted from the position in which they were origmally set and, in order to lock the cross head in the position to which it is set, ll provide the mechanism which I will now proceed to describe. i

18 is a rack bar attached to the cross head 3 and, in the present instance, locad under the guide 4. becured to the guide is a frame 19 in which is adapted to slide a clutch block 20 having teeth 21 which engage the teeth on the' rack 18 so that, when the teeth are in engagement, the rack and the cross head are rigidly attached to the guide and any leakage in the cylinder 1 will not alfect the piston.

rlhe block 20 is secured to a yoke 9 which extends over the' guide 4, and mounted between the upper en d of the yoke 9 and the frame 19 is a spring 22, which tends to force the block 20 away from the rack bar and in the frame 19 under the block 20 is a cylinder 23, a piston 24 in the cylinder rests against the underside of the block 20. An air pipe 25 is connected to the cylinder so that when air is introduced into the cylinder 23 it forces the block 20 into engagement with the rack 18, locking the rack until the pressure is relieved.

The pipe 25 is connected to any suitable reservoir, not shown, and a needle valve 26 regulates the amount of air admittedto the cylinder 23. Al pipe 27 is connected to the pipe 25 and leads to a valve 28 in the cab of the locomotive. This valve is made, as shown in Fig. 5, and has a casing provided with a seat 29 against which the valve proper 30 rests. A spring 31 normally holds the valve to its seat. rlhe valve closes against pressure in the pipe 27, but when A the valve is depressed, the pipe 27 is opened to the atmosphere and the air in the pipe escapes, relieving the cylinder 23 of pressure, and, consequently, allowing the spring 22 to force the block 20 .out of engagement with the rack 18.

Fivoted to an arm 32 on the casin of the valve 28 is a lever 33, one arm o which rests on the stem of the valve 30and the other arm is connected by a rod 34 to the handle 17, so that, when the handle is drawn toward the lever 13 to disengage it, the valve 28 is opened and the block is withdrawn from engagement with the rack so that the ,cross head and its piston can be moved to any point desired. Y

is a drain ,pipe which can be opened when desired.

When the starting lever is grasped by the engineer, he draws the arm 17 toward the lever, which opens the valve 28- and allows the air to escape from the pipe 27 and from thecylinder 23 which controls the block 20, and the spring -22 forces the block away from the rack 18. moved to the desired position and the piston Within the cylinder 1 and cross head 3 are correspondingly moved by the lever mechanism above described7 and, When the operator takes his hands off the arm 17, the air valve 28 is closed and the air in the pipe 25-passes the needle valve '26 and gradually lls the cylinder 23 and forces the teeth of the block 20 into engagement. with the rack, locking the rack, cross head, and its piston, in the position to which 'it has been set.

By making the plunger separate from the block, the block is independently guided, relievingthe plunger from. strain.

In Figs. 6, 7 and 8, I have villustrated a modificationr in Which the cylinder 23a' is located in thev frame 191 above the guide 4". The plunger 24a is located in this-cylinder and forms part of the yoke 36 Whichis, in turn, secured to the toothed block 37, the teeth of Which engage the rack bar 18a. The spring 22a is located Within the plunger and rests on the guide 4 pressure is admitted to the cylinder through the pipe 38, it forces the toothed block 37 out of contact with the rack bar-18, but, as

The lever 13 is then and When air undersoon as pressure is relieved, the spring forces the plate into engagement with the rack bar. l

An inlet valve, as shown in Fig. 8, is used in place of the exhaust valve shown in Fig. 5.

The combination in means for locking the reversing gear, of a cylinder; a piston therein; a 'rod attached to the piston; a guide; a cross-head arranged to slide on the guide and connected to the piston rod; a toothed bar attached to the cross-head and bearing against the guide; a frame` secured to'the guide; a toothed block arranged to engage the toothed bar, said block lbeing guided by the frame; a'plunger for moving the block toothed bar but Will be slowly engaged therewith.

In testimony whereof, I have signed my name to this specification, in the presence of -two subscribing Witnesses.

ELLWooD M. SHANNON.

Witnesses:

WM. E. SHURE, WM. A. BARR. 

